Author Topic: EM Drive Developments - related to space flight applications - Thread 11  (Read 223711 times)

Offline MadMarx

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Thank you for your answer!

I understand fairly well the non magical nature of "computer simulations".
My point was that as a black box capable of letting a new crazy theoretical framework in and producing out "Newtons of thrust", it could prove itself to be pretty useful to prove the theory exists and behaves as expected. If through in silico optimization you could produce a very obvious thrust model that if still isn't measured, should discredit the theory not the measurements.

In fact, it brings out a methodological problem: instead of trying to isolate an hypothesis (does the theory exist or not) people are testing a great many at once. The parameter space is too big. https://en.wikipedia.org/wiki/Look-elsewhere_effect
And for the Higgs Boson they even had the advantage of a high pretest expected probability of a non null hypothesis.

With the empiric "simulation" of airfoil aerodynamics the Wright Brothers had, they didn't do like Sonny and build a cube atop a railroad car to try to show microscopic lift, they tried to isolate their hypothesis, increase signal/noise ratio and make the thing fly.

With such a low pretest probability, I don't think "does it produce a microscopical force or not" is a good enough hypothesis. Using the theory to isolate the effect and make provable testable assumptions, is the way, is the only way science moves forward.

« Last Edit: 01/01/2019 11:28 am by MadMarx »

Online Monomorphic

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With the empiric "simulation" of airfoil aerodynamics the Wright Brothers had, they didn't do like Sonny and build a cube atop a railroad car to try to show microscopic lift, they tried to isolate their hypothesis, increase signal/noise ratio and make the thing fly.

MadMarx brings up a good point by reminding us that White claimed to have a virtual particle simulation model that predicted some of the measurement results with their frustum and mode. It would naturally follow that White should try altering the geometry and/or mode shape in the simulation to increase the efficiency - and then try to replicate that geometry and mode in a real experiment.
« Last Edit: 01/01/2019 02:30 pm by Monomorphic »

Offline dustinthewind

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With the empiric "simulation" of airfoil aerodynamics the Wright Brothers had, they didn't do like Sonny and build a cube atop a railroad car to try to show microscopic lift, they tried to isolate their hypothesis, increase signal/noise ratio and make the thing fly.

MadMarx brings up a good point by reminding us that White claimed to have a virtual particle simulation model that predicted some of the measurement results with their frustum and mode. It would naturally follow that White should try altering the geometry and/or mode shape in the simulation to increase the efficiency - and then try to replicate that geometry and mode in a real experiment.

Not only the shape but try modifying the frequencies.  I would like to see him try the frequency series to maximize unidirectional electron acceleration and the resulting effect. 
« Last Edit: 01/01/2019 05:09 pm by dustinthewind »

Offline demofsky

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Not only the shape but try modifying the frequencies.  I would like to see him try the frequency series to maximize unidirectional electron acceleration and the resulting effect.

YES!!  YES!!  This is the kind of thinking that needs to happen to move this forward!

Also transients need to be investigated (which could be frequency shifts but also power levels).  Both TT and Shell noticed significant results when they switched on their apparatus at one time or another.  This say to me that whatever is happening in those fustrums MAY be a nonlinear effect that is triggered by some type of transient effect that happens when they “flick the switch”.
« Last Edit: 01/02/2019 04:01 am by demofsky »

Offline Ricvil

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There is a symmetry where after a spatial radius inversion + translation + scaling, the transformed surface of conical cavity with flat end plates, becomes symmetric under a second spatial radius inversion around the translated central point.
Under this composed symmetry , I don't know the dependence of eigenfunctions, and resonant frequencys, related to the scaling parameter, but I'm thinking if internal fields must have many frequency components to follow this spatial scaling, and to reflect the composed symmetry of boundary conditions.
The spatial radius inversion is not the same of the special conformal transformations because time is not involved (except by the occurrence of some kind of event horizon),  but apparentely there is a curious relation with the dark  zones of superficial current under resonance conditions, related to the curvature of "inverted" surface.
PS: Just a remember, the surfaces are obtained by a rotation of contour around the axis of symmetry, and the signal of curvature of "inverted" surface will change in some regions. What are the corresponding regions at the untransformed surface?
PS2: Kenjee's Lorentizian cavity has two distinct small regions of changing signals of inverted surface curvature, one at  each side, at the neighborhood of end plates.
« Last Edit: 01/03/2019 08:56 pm by Ricvil »

Offline WarpTech

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With the empiric "simulation" of airfoil aerodynamics the Wright Brothers had, they didn't do like Sonny and build a cube atop a railroad car to try to show microscopic lift, they tried to isolate their hypothesis, increase signal/noise ratio and make the thing fly.

MadMarx brings up a good point by reminding us that White claimed to have a virtual particle simulation model that predicted some of the measurement results with their frustum and mode. It would naturally follow that White should try altering the geometry and/or mode shape in the simulation to increase the efficiency - and then try to replicate that geometry and mode in a real experiment.

White's team has been limited by both budget (there is none) and software capabilities. There is only so much they can do with COMSOL when it comes to simulating particle interactions.

That being said, there is very little evidence, if any, that electron-positron pairs in the vacuum occur naturally in such large numbers. Woodward published an article last year in JBIS refuting Sonny White's hypothesis. Personally, I don't see how a "practically" empty vacuum can be treated as a hydrodynamic system with any significant thrust. The e-p pairs should be proportional to the applied energy stored in the EM field, and it is a long way from the Schwinger limit. So the only place such particles could exist is within the metal.

Offline flux_capacitor

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With the empiric "simulation" of airfoil aerodynamics the Wright Brothers had, they didn't do like Sonny and build a cube atop a railroad car to try to show microscopic lift, they tried to isolate their hypothesis, increase signal/noise ratio and make the thing fly.

MadMarx brings up a good point by reminding us that White claimed to have a virtual particle simulation model that predicted some of the measurement results with their frustum and mode. It would naturally follow that White should try altering the geometry and/or mode shape in the simulation to increase the efficiency - and then try to replicate that geometry and mode in a real experiment.

White's team has been limited by both budget (there is none) and software capabilities. There is only so much they can do with COMSOL when it comes to simulating particle interactions.

That being said, there is very little evidence, if any, that electron-positron pairs in the vacuum occur naturally in such large numbers. Woodward published an article last year in JBIS refuting Sonny White's hypothesis. Personally, I don't see how a "practically" empty vacuum can be treated as a hydrodynamic system with any significant thrust. The e-p pairs should be proportional to the applied energy stored in the EM field, and it is a long way from the Schwinger limit. So the only place such particles could exist is within the metal.

Paul March explained here on NSF that Sonny White thinks indeed that a large amount of virtual particles do not "integrally" pop out of the vacuum to come 100% into "existence" as real particles (if such words have a physical meaning…) but instead could have a transitional state "not entirely virtual, not entirely real neither" that would increase their density.

Personally I tend to agree more with Woodward's statement in the JBIS paper you referred to. It sounds way more logical (and physical).

Offline RonM

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PBS Spacetime video describes why virtual particles don't work as a medium for EM drives. Starts at 5:45.

https://www.youtube.com/watch?v=Rh898Yr5YZ8?t=345

Offline Ricvil

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A cavity with two inverted surface curvature signal changing (shadowed), without scaling involved on inversion spheres (same radius), with almost spatial radius inversion symmetry of inverted surface and untransformed surface.
Conical and almost toroidal surface sections.
PS: I am giving a name to this cavity as "Owl Cavity".
« Last Edit: 01/13/2019 11:11 pm by Ricvil »

Offline X_RaY

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A cavity with two inverted curvature signal changing (shadowed), without scaling involved on inversion spheres (same radius), with spatial radius inversion symmetry of inverted surface and untransformed surface.
Conical and almost toroidal surface sections.

Ricvil, excuse me, but I guess you're the only one who understands what you mean. Could you please explain exactly what you are talking about? At best, in terms of scientific relations.
Which basis for any net thrust of such cavity do you propose?
« Last Edit: 01/07/2019 07:17 pm by X_RaY »

Offline Ricvil

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A cavity with two inverted curvature signal changing (shadowed), without scaling involved on inversion spheres (same radius), with spatial radius inversion symmetry of inverted surface and untransformed surface.
Conical and almost toroidal surface sections.

Ricvil, excuse me, but I guess you're the only one who understands what you mean. Could you please explain exactly what you are talking about? At best, in terms of scientific relations.
Which basis for any net thrust of such cavity do you propose?
Dear X_RaY,
Sorry about that.
At this point it is just a very complicated hypothesis.
Sometime ago, I've talked about to concentrate the radiation pressure at conical section of cavity, and to me this can be achieved using the intrinsic curvature of cavity boundary condition surface.
It is like to use a curved pipe to convert TE to TM modes, and vice versa,  but at a frequency where one of modes are not avaiable, then the "dark zones" arises. When the both modes are avaiable at the same frequency then they appears together.
But all this probably will produce just another photon rocket, except something more exotic is happening,
« Last Edit: 01/08/2019 03:25 pm by Ricvil »

Offline cvbn

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Offline Notsosureofit

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Interesting, but is there a formal paper with calculable details associated ?



LEMdrive:

http://physicsfromtheedge.blogspot.com/2016/07/lemdrive.html

https://www.rymdstyrelsen.se/contentassets/de067a79466749efa22b953340e47293/19.-investigation-of-propellant-less-propulsion-on-electromagnetic-resonant-cavities-em-drive.pdf

"There is a photon - thrust effect in the amplitude (4 times larger than noise level - third harmonic)"

Offline cvbn

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Offline meberbs

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LEMdrive:

http://physicsfromtheedge.blogspot.com/2016/07/lemdrive.html

https://www.rymdstyrelsen.se/contentassets/de067a79466749efa22b953340e47293/19.-investigation-of-propellant-less-propulsion-on-electromagnetic-resonant-cavities-em-drive.pdf

"There is a photon - thrust effect in the amplitude (4 times larger than noise level - third harmonic)"
That powerpoint presentation does not have enough information to make many conclusions, but it brings up a lot of questions.

For most of the graphs in it, I am not sure what they are supposed to be of, but some bring up major questions. One in particular shows "frequency versus temperature" has data points with error bars that are all over the place and best fit lines that don't even come close to passing within the error bars of most points. Another graph with unlabeled axes appears to show that the apparent trend does not care whether something is "on" or "off."

The data claims 0.04 uN/W, but then when calculating photon rocket forces, it uses 100mW, so that implies force was actually 4 nN. While not impossible to measure such a force, it would take an extremely good setup with very careful calibration, but there is no information to even determine what type of setup was used. Compared to the 4nN force measured, a photon rocket without reflection is 0.3 nN, and I question how if there is 100mW dissipated by some kind of current, that this would only correspond to magnetic force of 0.2nN, but again not enough information. Either way, forces about 1/10th of the measured signal do not count as "much smaller" especially when there are multiple of them and some (like photon thrust) can be amplified by reflections from the environment.

Basically a lot of words to say: There is so little information in the plain slides, they don't communicate much, but even if this is just initial work for a later paper, it brings up many more questions than answers.

Offline RERT

The powerpoint prompted me to wonder what level of performance above a photon-rocket would actually be of any use. I don't recall (but may have forgotten) any conversation about this before on the Emdrive thread.

Judging by what google tells me about cubesat thrusters, it looks to me as if 1 μN/W would be useful, if cheap and light enough to replace a 0.6U cubesat thruster. So roughly a few hundred times a photon-rocket. Maybe notably less if the ability to thrust 'forever' is taken into account.

Any other opinions? Are there any other missions made feasible by a lower propellant-less thrust?


Offline Star One

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There doesn’t seem to have been any reporting of this news that I can see outside of those links above?

Offline MathewOrman

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Offline meberbs

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Orman Force Drive https://www.youtube.com/watch?v=lhldn0ef138&feature=youtu.be
Try posting a link to a pdf, rather than a painfully formatted youtube video of a pdf.

Also, the Lorentz force works and has been measured and confirmed by countless experiments. Go study some basic electrodynamics before making absurd claims to the contrary. There are some unintuitive aspects to electrodynamics, and they only all make sense together when considered alongside special relativity, and energy and momentum being present inside of fields (which ties to massless particles in special relativity.)

Offline hyperplanck

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a photon rocket without reflection is 0.3 nN,

May I ask for your source of this assertion and your logical reasoning to its sigma validity as an absolute value?

I did a little recent searching, on some of the papers published for force of a photon, but from reassessing myself to this fields subject matter, it seems to be a very immature understanding of the subject, without a general consensus to spatial and time Planck scale considerations. This abstract understanding of the values of photons pressure/force is especially the case for complex mediums.

A cavity-confined qubit can register the reflection of a single microwave photon without destroying it.
https://physics.aps.org/articles/v11/38

Experimental evidence for Abraham pressure of light
"the momentum transfer of light in fluids is truly Janus–faced: the Minkowski or the Abraham momentum can emerge in similar experiments. The Abraham momentum, equation (2), emerges as the optomechanical momentum when the fluid is moving and the Minkowski momentum, equation (1), when the light is too focused or the container too small to set the fluid into motion."
http://iopscience.iop.org/article/10.1088/1367-2630/17/5/053035
https://phys.org/news/2015-06-physicists-pressure.html

Nanonewton force generation and detection based
on a sensitive torsion pendulum
Sheng-Jui Chen and Sheau-Shi Pan
"Converting to force
by 70 mm torque armlength and the spring constant
of the pendulum, the force is 4.9 ± 0.4 nN which is in
good agreement with the prediction."
https://arxiv.org/pdf/0806.3300.pdf

Comparison of electrostatic and photon pressure force references at the nanonewton level:
Accepted Manuscript online 19 December 2018
"This work demonstrates a method to link mass, force and laser power within the International System of Units with explicit treatment of absorption, diffuse reflection, and a detailed uncertainty analysis. Additionally, it demonstrates a viable method to scale this force continuously using a pulsed laser technique while maintaining the constant thermal load necessary for precision measurement of nanonewton forces with a mechanical balance."
http://iopscience.iop.org/article/10.1088/1681-7575/aaf9c2/pdf


A self-calibrating optomechanical force sensor with femtonewton resolution
John Melcher,∗ Julian Stirling, Felipe Guzm´an Cervantes, Jon R. Pratt, and Gordon A. Shaw
National Institute of Standards and Technology
Physical Measurement Laboratory
(Dated: October 5, 2018)
"We observe two distinct distributions of 626 ± 7 fN
and 780 ± 7 fN, where the uncertainty quoted represents
one standard deviation of the measurements. Including
the uncertainty in the calibration, the combined standard
uncertainty estimate becomes ±9 fN [30]. Since the distributions of the force measurements are approximately
Gaussian, we conservatively estimate a force resolution
of approximately 14 fN. It is important to note that this
resolution is achieved with a stiff sensor that is suitable
for atomic-resolution AFM, as opposed to low stiffness
MRFM sensors [6] or nanowires [25].
https://arxiv.org/pdf/1410.5725.pdf
« Last Edit: 01/14/2019 01:20 am by hyperplanck »

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